The invention relates to an electric lamp of the type having a light source within a lamp vessel which is sealed in a vacuum-tight manner has a pinched seal at one end. The lamp vessel may consist of glass having an SiO.sub.2 content of at least 95% by weight.
At least one metal foil with a first and a second end accommodated in the pinched seal serves as current lead-through conductor, the metal foil is connected near its first end to an internal current conductor extending to the light source and connected near its second end to several external current conductors emanating from the pinched seal.
The pinched seal being fixed in a said lamp cap provided with an electrical contact.
A current supply wire or conductor connected to the electrical contact of the lamp cap and to the said several external current conductors. Such an electric lamp is known from U.S. Pat. No. 4 499 404.
The known lamp is an incandescent lamp having only one pinched seal, in which two metal foils are accommodated, which are each connected to a respective internal current conductor and to a respective pair of external current conductors. At right angles to the external current conductors a respective current supply wire is welded to each pair of external current conductors.
By using more than one external current conductor per metal foil, the current density in the external current conductors and in the welds of said conductors to the metal foils is decreased and hence the heat development in the pinched seal is reduced.
As the number of external current conductor is larger, however, the risk is greater than they are not all located in a flat plane. When welding connections are made, external current conductors can then be elastically deformed, as a result of which they produce mechanical stresses in the pinched seal. These stresses can lead to rupture of the pinched seal and to leakage of the gas fill from the lamp vessel.